Photographic Triad Shot Count
Definition
Minimum examiners-favoured rule: three shots per item of evidence (overall, mid-range, close-up with scale) plus one close-up without scale. The without-scale frame defeats the defence claim that the scale obstructed an important detail.
- Base sequence
- Overall, mid-range, close-up with scale
- Added frame
- One close-up without scale
- Total minimum
- Four photographs per item
- Purpose of extra frame
- Rebuts claim that scale obscured detail
Common questions
Why photograph the same close-up twice, with and without scale?+
A scale placed directly over or beside an evidentiary mark can be argued in court to have hidden a relevant feature. The without-scale frame proves the detail was fully visible before the scale was introduced, closing off that line of challenge.
Is the without-scale frame taken before or after the scaled one?+
Convention is to shoot the unscaled close-up first, then add the scale for the measured frame, so the evidence is documented in its untouched state before anything is placed on or near it.
Related terms
- ABFO #2 Scale
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- BSA 2023 Section 63
- Bharatiya Sakshya Adhiniyam 2023 Section 63 (the successor to Section 65B of the Indian Evidence Act 1872): the electronic-record certificate that authenticates...
- Oblique Flash
- Off-camera flash held at a low angle (typically 15 to 30 degrees) to the surface plane. Used to highlight impressed evidence (tool...
- Photogrammetry
- A technique that uses overlapping photographs to reconstruct three-dimensional geometry from two-dimensional images. In forensic engineering, photogrammetry and Structure-from-Motion (SfM) software allow...
- Photographic Triad
- The mandatory three-shot sequence for every piece of crime-scene evidence: overall (wide context), mid-range (relational to a fixed scene landmark), close-up (macro...
- RAW Capture
- Lossless sensor-data file format (Nikon NEF, Canon CR2/CR3, Sony ARW). Preserves the unprocessed image for evidentiary integrity, allows non-destructive white-balance and exposure...